Datasheet LM4041DIM3-ADJ, LM4041CIM3-ADJ, LM4041CIM3-1.2, LM4040CIM3-5.0, LM4040CIM3-2.5 Datasheet (MICREL)

LM4040/4041 Micrel

LM4040/4041

Precision Micropower Shunt Voltage Reference

General Description

Ideal for space critical applications, the LM4040 and LM4041
precision voltage references are available in the subminia­ture (3mm × 1.3mm) SOT-23 surface-mount package.

The LM4040 is the available in fixed reverse breakdown
voltages of 2.500V, 4.096V and 5.000V. The LM4041 is
available with a fixed 1.225V or an adjustable reverse break­down voltage.

The LM4040 and LM4041’s advanced design eliminates the
need for an external stabilizing capacitor while ensuring
stability with any capacitive load, making them easy to use.

The minimum operating current ranges from 60µA for the
LM4041-1.2 to 74µA for the LM4040-5.0. LM4040 versions
have a maximum operating current of 15mA. LM4041
versions have a maximum operating current of 12mA.

The LM4040 and LM4041 utilizes zener-zap reverse break­down voltage trim during wafer sort to ensure that the prime
parts have an accuracy of better than ±0.1% (A grade) at
25°C. Bandgap reference temperature drift curvature correc­tion and low dynamic impedance ensure stable reverse
breakdown voltage accuracy over a wide range of operating
temperatures and currents.

Features

• Small SOT-23 package

• No output capacitor required

• Tolerates capacitive loads

• Fixed reverse breakdown voltages of 1.225, 2.500V,

4.096V and 5.000V

• Adjustable reverse breakdown version

• Contact Micrel for parts with extended temperature
range.

Key Specifications

• Output voltage tolerance (A grade, 25°C) .. ±0.1% (max)

• Low output noise (10Hz to 100Hz)

LM4040 ................................................35µV

LM4041 ................................................20µV

RMS
RMS

(typ)
(typ)

• Wide operating current range

LM4040 ................................................ 60µA to 15mA

LM4041 ................................................ 60µA to 12mA

• Industrial temperature range ..................–40°C to +85°C

• Low temperature coefficient ................100ppm/°C (max)

Applications

• Battery-Powered Equipment

• Data Acquisition Systems

• Instrumentation

• Process Control

• Energy Management

• Product Testing

• Automotive Electronics

• Precision Audio Components

Typical Applications

V

S

V

S

IQ + I

R

S

V

R

LM4040
LM4041

Figure 1. LM4040, LM4041 Fixed

Shunt Regulator Application

Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 [phone] • fax + 1 [phone] • http://www.micrel.com

L

I

L

V

O

I

Q

Adjustable

Figure 2. LM4041 Adjustable

Shunt Regulator Application

January 2000 1 LM4040/4041

LM4041

R

S

V

R

V

O

R

1

VO = 1.233 (R2/R1 + 1)

R

2

LM4040/4041 Micrel

Pin Configuration

1

+

3

–

2

Pin 3 must float or

be connected to pin 2.

Fixed Version

SOT-23 (M3) Package

Top View

Ordering Information

Part Number * Voltage Accuracy,

Temp. Coefficient

LM4040AIM3-2.5 2.500V ±0.1%, 100ppm/°C
LM4040BIM3-2.5 2.500V ±0.2%, 100ppm/°C
LM4040CIM3-2.5 2.500V ±0.5%, 100ppm/°C
LM4040DIM3-2.5 2.500V ±1.0%, 150ppm/°C
LM4040AIM3-4.1 4.096V ±0.1%, 100ppm/°C
LM4040BIM3-4.1 4.096V ±0.2%, 100ppm/°C
LM4040CIM3-4.1 4.096V ±0.5%, 100ppm/°C
LM4040DIM3-4.1 4.096V ±1.0%, 150ppm/°C
LM4040AIM3-5.0 5.000V ±0.1%, 100ppm/°C
LM4040BIM3-5.0 5.000V ±0.2%, 100ppm/°C
LM4040CIM3-5.0 5.000V ±0.5%, 100ppm/°C
LM4040DIM3-5.0 5.000V ±1.0%, 150ppm/°C

1

FB

3 –

+

2

Adjustable Version

SOT-23 (M3) Package

Top View

Part Number * Voltage Accuracy,

Temp. Coefficient

LM4041AIM3-1.2 1.225V ±0.1%, 100ppm/°C
LM4041BIM3-1.2 1.225V ±0.2%, 100ppm/°C
LM4041CIM3-1.2 1.225V ±0.5%, 100ppm/°C
LM4041DIM3-1.2 1.225V ±1.0%, 150ppm/°C
LM4041CIM3-ADJ 1.24V to 10V ±0.5%, 100ppm/°C
LM4041DIM3-ADJ 1.24V to 10V ±1.0%, 150ppm/°C

SOT-23 Package Markings

Example Field Code

R _ _ 1st Character R = Reference

Example: R2C represents

±

0.5%

(LM4040CIM3-2.5)

Reference, 2.500V,

LM4040/4041 2 January 2000

Example Field Code

_ 2 _ 2nd Character 1 = 1.225V

2 = 2.500V
4 = 4.096V
5 = 5.000V
A = Adjustable

Example Field Code

_ _ A 3rd Character A = ±0.1%

B = ±0.2%
C = ±0.5%
D = ±1.0%

Note: If 3rd character is omitted, container will
indicate tolerance.

LM4040/4041 Micrel

Functional Diagram
LM4040, LM4041 Fixed

Functional Diagram
LM4041 Adjustable

+

V

REF

FB

+

Absolute Maximum Ratings

Reverse Current.........................................................20mA

Forward Current .........................................................10mA

Maximum Output Voltage

LM4041-Adjustable ...................................................15V

Power Dissipation at TA = 25°C (Note 2) ................306mW

Storage Temperature ............................... –65°C to +150°C

Lead Temperature

Vapor phase (60 seconds) .............................. +215°C

Infrared (15 seconds) ...................................... +220°C

ESD Susceptibility

Human Body Model (Note 3).................................2kV

Machine Model (Note 3) ......................................200V

Operating Ratings (Notes 1 and 2)

Temperature Range

(T

≤ TA ≤ T

MIN

Reverse Current

LM4040-2.5 .......................................... 60µA to 15mA

LM4040-4.1 .......................................... 68µA to 15mA

LM4040-5.0 .......................................... 74µA to 15mA

LM4041-1.2 .......................................... 60µA to 12mA

LM4041-ADJ ........................................ 60µA to 12mA

Output Voltage Range

LM4041-ADJ .......................................... 1.24V to 10V

).......................... –40°C ≤ TA ≤ +85°C

MAX

January 2000 3 LM4040/4041

LM4040/4041 Micrel

LM4040-2.5 Electrical Characteristics

Boldface limits apply for TA = TJ = T

Breakdown Voltage tolerance of ±0.1%, ±0.2%, ±0.5%, and ±1.0 respectively.

Symbol Parameter Conditions Typical Units

V

R

Reverse Breakdown Voltage IR = 100µA 2.500 V
Reverse Breakdown Voltage I

Tolerance ±19 ±21 ±29 mV (max)

I

RMIN

∆V

R

Minimum Operating Current 45 µA

/∆T Average Reverse Breakdown IR = 10mA 20 ppm/°C

Voltage Temperature I
Coefficient IR = 100µA 15 ppm/°C (max)

/∆IRReverse Breakdown Voltage I

∆V

R

Change with Operating 0.8 0.8 0.8 mV (max)
Current Change 1.0 1.0 1.0 mV (max)

Z

e

∆V

R

N

R

Reverse Dynamic Impedance IR = 1mA, f = 120Hz 0.3 Ω

Wideband Noise IR = 100µA

Reverse Breakdown Voltage t = 1000hrs
Long Term Stability T = 25°C ±0.1°C 120 ppm

MIN

to T

; all other limits TA = TJ = 25°C. The grades A, B, C, and D designate initial Reverse

MAX

LM4040AIM3 LM4040BIM3 LM4040CIM3

(Note 4) Limits Limits Limits (Limit)

(Note 5) (Note 5) (Note 5)

= 100µA ±2.5 ±5.0 ±12 mV (max)

R

60 60 60 µA (max)
65 65 65 µA (max)

= 1mA 15 100 100 100 ppm/°C (max)

R

≤ IR 1mA 0.3 mV

RMIN

1mA ≤ I

15mA 2.5 mV

R

0.6 0.6 0.6 mV (max)

8.0 8.0 8.0 mV (max)

IAC = 0.1 I

R

0.8 0.8 0.9 Ω (max)

10Hz ≤ f ≤ 10kHz 35 µV

IR = 100µA

RMS

Symbol Parameter Conditions Typical Units

LM4040DIM3

(Note 4) Limits (Limit)

(Note 5)

V

R

I

RMIN

Reverse Breakdown Voltage IR = 100µA 2.500 V
Reverse Breakdown Voltage I

Tolerance ±49 mV (max)

= 100µA ±25 mV (max)

R

Minimum Operating Current 45 µA

65 µA (max)
70 µA (max)

/∆T Average Reverse Breakdown IR = 10mA 20 ppm/°C

∆V

R

Voltage Temperature I
Coefficient IR = 100µA 15 ppm/°C (max)

/∆IRReverse Breakdown Voltage I

∆V

R

Change with Operating 1.0 mV (max)

= 1mA 15 150 ppm/°C (max)

R

≤ IR 1mA 0.3 mV

RMIN

Current Change 1.2 mV (max)

1mA ≤ I

15mA 2.5 mV

R

8.0 mV (max)

10.0 mV (max)

Z

e

∆V

R

N

R

Reverse Dynamic Impedance IR = 1mA, f = 120Hz 0.3 Ω

IAC = 0.1 I

R

1.1 Ω (max)

Wideband Noise IR = 100µA

10Hz ≤ f ≤ 10kHz 35 µV

RMS

Reverse Breakdown Voltage t = 1000hrs
Long Term Stability T = 25°C ±0.1°C 120 ppm

IR = 100µA

LM4040/4041 4 January 2000

LM4040/4041 Micrel

LM4040-4.1 Electrical Characteristics

Boldface limits apply for TA = TJ = T

Breakdown Voltage tolerance of ±0.1%, ±0.2%, ±0.5%, and ± 1.0% respectively.

Symbol Parameter Conditions Typical Units

V

R

Reverse Breakdown Voltage IR = 100µA 4.096 V
Reverse Breakdown Voltage I

Tolerance ±31 ±35 mV (max)

I

RMIN

∆V

R

Minimum Operating Current 50 µA

/∆T Average Reverse Breakdown IR = 10mA 30 ppm/°C

Voltage Temperature I
Coefficient IR = 100µA 20 ppm/°C (max)

/∆IRReverse Breakdown Voltage I

∆V

R

Change with Operating 0.9 0.9 mV (max)
Current Change 1.2 1.2 mV (max)

Z

e

∆V

R

N

R

Reverse Dynamic Impedance IR = 1mA, f = 120Hz 0.5 Ω

Wideband Noise IR = 100µA

Reverse Breakdown Voltage t = 1000hrs
Long Term Stability T = 25°C ±0.1°C 120 ppm

MIN

to T

; all other limits TA = TJ = 25°C. The grades A, B, C, and D designate initial Reverse

MAX

LM4040AIM3 LM4040BIM3

(Note 4) Limits Limits (Limit)

(Note 5) (Note 5)

= 100µA ±4.1 ±8.2 mV (max)

R

68 68 µA (max)
73 73 µA (max)

= 1mA 20 100 100 ppm/°C (max)

R

≤ IR 1mA 0.5 mV

RMIN

1mA ≤ I

15mA 3.5 mV

R

7.0 7.0 mV (max)

10.0 10.0 mV (max)

IAC = 0.1 I

R

1.0 1.0 Ω (max)

10Hz ≤ f ≤ 10kHz 80 µV

IR = 100µA

RMS

Symbol Parameter Conditions Typical Units

LM4040CIM3 LM4040DIM3

(Note 4) Limits Limits (Limits)

(Note 5) (Note 5)

V

R

I

RMIN

Reverse Breakdown Voltage IR = 100µA 4.096 V
Reverse Breakdown Voltage I

Tolerance ±47 ±81 mV (max)

= 100µA ±20 ±41 mV (max)

R

Minimum Operating Current 50 µA

68 73 µA (max)
73 78 µA (max)

/∆T Average Reverse Breakdown IR = 10mA 30 ppm/°C

∆V

R

Voltage Temperature I
Coefficient IR = 100µA 20 ppm/°C (max)

/∆IRReverse Breakdown Voltage I

∆V

R

Change with Operating 0.9 1.2 mV (max)

= 1mA 20 100 150 ppm/°C (max)

R

≤ IR 1mA 0.5 mV

RMIN

Current Change 1.2 1.5 mV (max)

1mA ≤ I

15mA 3.0 mV

R

7.0 9.0 mV (max)

10.0 13.0 mV (max)

Z

e

∆V

R

N

R

Reverse Dynamic Impedance IR = 1mA, f = 120Hz 0.5 Ω

IAC = 0.1 I

R

1.0 1.3 Ω (max)

Wideband Noise IR = 100µA

10Hz ≤ f ≤ 10kHz 80 µV

RMS

Reverse Breakdown Voltage t = 1000hrs
Long Term Stability T = 25°C ±0.1°C 120 ppm

IR = 100µA

January 2000 5 LM4040/4041

LM4040/4041 Micrel

LM4040-5.0 Electrical Characteristics

Boldface limits apply for TA = TJ = T

Breakdown Voltage tolerance of ±0.1%, ±0.2%, ±0.5%, and ± 1.0% respectively.

Symbol Parameter Conditions Typical Units

V

R

Reverse Breakdown Voltage IR = 100µA 5.000 V
Reverse Breakdown Voltage I

Tolerance ±38 ±43 mV (max)

I

RMIN

∆V

R

Minimum Operating Current 54 µA

/∆T Average Reverse Breakdown IR = 10mA 30 ppm/°C

Voltage Temperature I
Coefficient IR = 100µA 20 ppm/°C (max)

/∆IRReverse Breakdown Voltage I

∆V

R

Change with Operating 1.0 1.0 mV (max)
Current Change 1.4 1.4 mV (max)

Z

e

∆V

R

N

R

Reverse Dynamic Impedance IR = 1mA, f = 120Hz 0.5 Ω

Wideband Noise IR = 100µA

Reverse Breakdown Voltage t = 1000hrs
Long Term Stability T = 25°C ±0.1°C 120 ppm

MIN

to T

; all other limits TA = TJ = 25°C. The grades A, B, C, and D designate initial Reverse

MAX

LM4040AIM3 LM4040BIM3

(Note 4) Limits Limits (Limit)

(Note 5) (Note 5)

= 100µA ±5.0 ±10 mV (max)

R

74 74 µA (max)
80 80 µA (max)

= 1mA 20 100 100 ppm/°C (max)

R

≤ IR 1mA 0.5 mV

RMIN

1mA ≤ I

15mA 3.5 mV

R

8.0 8.0 mV (max)

12.0 12.0 mV (max)

IAC = 0.1 I

R

1.1 1.1 Ω (max)

10Hz ≤ f ≤ 10kHz 80 µV

IR = 100µA

RMS

Symbol Parameter Conditions Typical Units

LM4040CIM3 LM4040DIM3

(Note 4) Limits Limits (Limits)

(Note 5) (Note 5)

V

R

I

RMIN

Reverse Breakdown Voltage IR = 100µA 5.000 V
Reverse Breakdown Voltage I

Tolerance ±58 ±99 mV (max)

= 100µA ±25 ±50 mV (max)

R

Minimum Operating Current 54 µA

74 79 µA (max)
80 85 µA (max)

/∆T Average Reverse Breakdown IR = 10mA 30 ppm/°C

∆V

R

Voltage Temperature I
Coefficient IR = 100µA 20 ppm/°C (max)

/∆IRReverse Breakdown Voltage I

∆V

R

Change with Operating 1.0 1.3 mV (max)

= 1mA 20 100 150 ppm/°C (max)

R

≤ IR 1mA 0.5 mV

RMIN

Current Change 1.3 1.8 mV (max)

1mA ≤ I

15mA 3.5 mV

R

8.0 10.0 mV (max)

12.0 15.0 mV (max)

Z

e

∆V

R

N

R

Reverse Dynamic Impedance IR = 1mA, f = 120Hz 0.5 Ω

IAC = 0.1 I

R

1.1 1.5 Ω (max)

Wideband Noise IR = 100µA

10Hz ≤ f ≤ 10kHz 80 µV

RMS

Reverse Breakdown Voltage t = 1000hrs
Long Term Stability T = 25°C ±0.1°C 120 ppm

IR = 100µA

LM4040/4041 6 January 2000

LM4040/4041 Micrel

LM4040 T ypical Characteristics

Temperature Drift for Different

Average Temperature Coefficient

+0.5
+0.4
+0.3
+0.2
+0.1

0

-0.1

CHANGE (%)

R

-0.2

V

-0.3

-22ppm/°C

-0.4

-0.5

-40

-200 20406080100
TEMPERATURE (°C)

IR = 150µA

12ppm/°C

-51ppm/°C

Reverse Characteristics and

Minimum Operating Current

120
100

80
60
40
20

REVERSE CURRENT (µA)

0

0 2 4 6 8 10

1k

100

VR = 5V

10

IMPEDANCE (Ω)

1

0.1
100 1k 10k 100k 1M

5V

2.5V

4.1V

Guaranteed

D Suffix

I

RMIN

A, B, C, Suffix

•

•

•

Typical

TJ = 25°C

REVERSE VOLTAGE (V)

Output Impedance

vs. Frequency

IR = I

+ 100 µA

RMIN

= 25 °C, ∆ I

T

J

2.5V

FREQUENCY (Hz)

•

R

= 0.1 I

R

C

= 0

L

C

= 1µF

L

TANTALUM

IMPEDANCE (Ω)

X

CL

Noise Voltage
vs. Frequency

10.0

5.0

2.0

√

1.0

0.5

Noise (µV/ Hz )

0.2

0.1
1 10 100 1k 10k 100k

FREQUENCY (Hz)

Output Impedance

vs. Frequency

1k

100

10

1

0.1
100 1k 10k 100k 1M

IR = 200µA

T

= 25°C

J

5V

2.5V

IR= 1mA

= 25 °C, ∆IR = I

T

J

VR = 5V

2.5V

FREQUENCY (Hz)

CL= 1µF

TANTALUM

R

CL= 0

1Hz rate

LM4040-2.5 RS = 30k

5

(V)

IN

0

6
4

(V) V

R

2

V

0

0 20 40 60 80

RESPONSE TIME (µs)

V

IN

IJ = 25°C

R

S

LM4040

Test Circuit

(V)
V

(V)

R

V

V

R

LM4040-5.0 RS = 30k

10

IN

0

6
4
2
0

0 100 200 300 400

RESPONSE TIME (µs)

TJ = 25°C

January 2000 7 LM4040/4041

LM4040/4041 Micrel

LM4041-1.2 Electrical Characteristics

Boldface limits apply for TA = TJ = T

Breakdown Voltage tolerance of ±0.1%, ±0.2%, ±0.5%, and ± 1.0%, respectively.

Symbol Parameter Conditions Typical Units

V

R

Reverse Breakdown Voltage IR = 100µA 1.225 V
Reverse Breakdown Voltage I

Tolerance ±9.2 ±10.4 ±14 mV (max)

I

RMIN

∆V

R

Minimum Operating Current 45 µA

/∆T Average Reverse Breakdown IR = 10mA 20 ppm/°C

Voltage Temperature I
Coefficient IR = 100µA 15 ppm/°C (max)

/∆IRReverse Breakdown Voltage I

∆V

R

Change with Operating 1.5 1.5 1.5 mV (max)
Current Change 2.0 2.0 2.0 mV (max)

Z

e

∆V

R

N

R

Reverse Dynamic Impedance IR = 1mA, f = 120Hz 0.5 Ω

Wideband Noise IR = 100µA

Reverse Breakdown Voltage t = 1000hrs
Long Term Stability T = 25°C ±0.1°C 120 ppm

MIN

to T

; all other limits TA = TJ = 25°C. The grades A, B, C, and D designate initial Reverse

MAX

LM4041AIM3 LM4041BIM3 LM4041CIM3

(Note 4) Limits Limits Limits (Limit)

(Note 5) (Note 5) (Note 5)

= 100µA ±1.2 ±2.4 ±6 mV (max)

R

60 60 60 µA (max)
65 65 65 µA (max)

= 1mA 15 ±100 ±100 ±100 ppm/°C (max)

R

≤ IR 1mA 0.7 mV

RMIN

1mA ≤ I

15mA 4.0 mV

R

6.0 6.0 6.0 mV (max)

8.0 8.0 8.0 mV (max)

IAC = 0.1 I

R

1.5 1.5 1.5 Ω (max)

10Hz ≤ f ≤ 10kHz 20 µV

IR = 100µA

RMS

Symbol Parameter Conditions Typical Units

LM4041DIM3 LM4041EIM3

(Note 4) Limits Limits (Limit)

(Note 5) (Note 5)

V

R

I

RMIN

Reverse Breakdown Voltage IR = 100µA 1.225 V
Reverse Breakdown Voltage I

Tolerance ±24 ±36 mV (max)

= 100µA ±12 ±25 mV (max)

R

Minimum Operating Current 45 µA

65 65 µA (max)
70 70 µA (max)

/∆T Average Reverse Breakdown IR = 10mA 20 ppm/°C

∆V

R

Voltage Temperature I
Coefficient IR = 100µA 15 ppm/°C (max)

/∆IRReverse Breakdown Voltage I

∆V

R

Change with Operating 2.0 2.0 mV (max)

= 1mA 15 ±150 ±150 ppm/°C (max)

R

≤ IR 1mA 0.3 mV

RMIN

Current Change 2.5 2.5 mV (max)

1mA ≤ I

15mA 2.5 mV

R

8.0 8.0 mV (max)

10.0 10.0 mV (max)

Z

e

∆V

R

N

R

Reverse Dynamic Impedance IR = 1mA, f = 120Hz 0.3 Ω

IAC = 0.1 I

R

2.0 2.0 Ω (max)

Wideband Noise IR = 100µA

10Hz ≤ f ≤ 10kHz 35 µV

RMS

Reverse Breakdown Voltage t = 1000hrs
Long Term Stability T = 25°C ±0.1°C 120 ppm

IR = 100µA

LM4040/4041 8 January 2000

LM4040/4041 Micrel

LM4041-Adjustable Electrical Characteristics

Boldface limits apply for TA = TJ = T

I

≤ IR < 12mA, V

RMIN

±1%, respectively for V

REF

≤ V

OUT

≤ 10V. The grades C and D designate initial Reverse Breakdown Voltage tolerance of ±0.5% and

OUT

= 5V.

Symbol Parameter Conditions Typical Units

V

REF

Reference Breakdown Voltage IR = 100µA 1.233 V

Reference Breakdown Voltage IR = 100µA ±6.2 ±12 mV (max)
Tolerance (Note 8) ±14 ±24 mV (max)

I

RMIN

∆V

REF

/∆I

R

∆V

REF

/∆V

I

FB

∆V

REF

/∆T Voltage Temperature I

Minimum Operating Current 45 µA

Reference Voltage I
Change with Operating SOT-23: 1.5 2.0 mV (max)
Current Change V

Reference Voltage Change IR = 1mA –1.3 mV/V
with Output Voltage Change –2.0 –2.5 mV/V (max)

O

Feedback Current 60 nA

Average Reference V
Coefficient I

(Note 8) IR = 100µA 15 ppm/°C (max)

Z

e

∆V

OUT

N

REF

Dynamic Output Impedance IR = 1mA, f = 120Hz

Wideband Noise IR = 100µA

Reference Voltage t = 1000hrs
Long Term Stability T = 25°C ±0.1°C 120 ppm

MIN

to T

; all other limits TJ = 25°C unless otherwise specified (SOT-23, see Note 7),

MAX

LM4041CIM3 LM4041DIM3

(Note 4) Limits Limits (Limit)

(Note 5) (Note 5)

V

= 5V

OUT

60 65 µA (max)
65 70 µA (max)

≤ IR 1mA 0.7 mV

RMIN

≥ 1.6V 2.0 2.5 mV (max)

OUT

(Note 7)
1mA ≤ I

SOT-23: 4 6 mV (max)

15mA 2 mV

R

≥ 1.6V 68mV (max)

V

OUT

(Note 7)

–2.5 –3.0 mV/V (max)

100 150 nA (max)
120 200 nA (max)

= 5V

OUT

= 10mA 20 ppm/°C

R

= 1mA 15 ±100 ±150 ppm/°C (max)

R

= 0.1 I

I

AC

R

V

= V

V

OUT
OUT

REF

= 10V 2 Ω (max)

0.3 Ω

10Hz ≤ f ≤ 10kHz 20 µV

IR = 100µA

RMS

January 2000 9 LM4040/4041

LM4040/4041 Micrel

LM4040 and LM4041 Electrical Characteristic Notes

Note 1. Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the

Note 2. The maximum power dissipation must be derated at elevated temperatures and is dictated by T

Note 3. The human body model is a 100pF capacitor discharged through a 1.5kΩ resistor into each pin. The machine model is a 200pF capacitor

Note 4. Typicals are at TJ = 25°C and represent most likely parametric norm.
Note 5. Limits are 100% production tested at 25°C. Limits over temperature are guaranteed through correlation using Statistical Quality Control (SQL)

Note 6. The boldface (over temperature limit for Reverse Breakdown Voltage Tolerance is defined as the room temperature Reverse Breakdown

Note 7. When V

Note 8. Reference voltage and temperature coefficient will change with output voltage. See Typical Performance Characteristics curves.

device is functional, but do not guarantee specific performance limits. For guaranteed specification and test conditions, see the Electrical
Characteristics. The guaranteed specifications apply only for the test conditions listed. Some performance characteristics may degrade when
the device is not operated under the listed test conditions.

(maximum junction temperature), θ

(junction to ambient thermal resistance), and TA (ambient temperature). The maximum allowable power dissipation at any temperature is

= (T

PD

MAX

T

= 125°C, and the typical thermal resistance (θJA), when board mounted, is 326°C/W for the SOT-23 package.

JMAX

– TA)/θJA or the number given in the Absolute Maximum Ratings, whichever is lower. For the LM4040 and LM4041,

JMAX

JMAX

JA

discharged directly into each pin.

methods.

Voltage Tolerance ±[(∆VR/∆T)(65°C)(VR)]. ∆VR/∆T is the VR temperature coefficient, 65°C is the temperature range from –40°C to the
reference point of 25°C, and VR is the reverse breakdown voltage. The total over temperature tolerance for the different grades follows:

A-grade: ±0.75% = ±0.1% ±100ppm/°C × 65°C
B-grade: ±0.85% = ±0.2% ±100ppm/°C × 65°C
C-grade: ±1.15% = ±0.5% ±100ppm/°C × 65°C
D-grade: ±1.98% = ±1.0% ±150ppm/°C × 65°C

Example: The A-grade LM4040-2.5 has an over temperature Reverse Breakdown Voltage tolerance of ±2.5 × 0.75% = ±19mV.

≤ 1.6V, the LM4041-ADJ must operate at reduced IR. This is caused by the series resistance of the die attach between the die (–)

OUT

output and the package (–) output pin. See the Output Saturation curve in the Typical Performance Characteristics section.

LM4041 T ypical Characteristics

Temperature Drift for Different

Average Temperature Coefficient

+0.5
+0.4
+0.3
+0.2
+0.1

0

-0.1

CHANGE (%)

R

-0.2

V

-0.3

-0.4

-0.5

-40

-22ppm/°C

-200 20406080100
TEMPERATURE (°C)

Reverse Characteristics and

Minimum Operating Current

100

80

60

40

20

REVERSE CURRENT (µA)

0

0 0.4 0.8 1.2 1.6 2.0

REVERSE VOLTAGE (V)

LM4041-1.2

12ppm/°C

-51ppm/°C

IR = 150µA

Typical

= 25°C

T

J

LM4041-1.2

Output Impedence

vs. Frequency

1k

100

10

I

R

IMPEDANCE (Ω)

1

I

0.1
100 1k 10k 100k 1M

TJ = 25° C
∆I
LM4041-1.2

= 150µA

= 1mA

R

FREQUENCY (Hz)

R

= 0.1I

R

Reverse Characteristics and
Minimum Operating Current

100

80

60

40

20

REVERSE CURRENT (µA)

0

0 0.4 0.8 1.2 1.6 2.0

REVERSE VOLTAGE (V)

Typical
T

J

LM4041-1.2

CL= 0

CL= 1µF

TANTALUM

X

= 25°C

Voltage Impedance

1000

800

√

600

400

NOISE (nV/ Hz )

200

C

LM4041-ADJ: V

0

1 10 100 1k 10k 100k

FREQUENCY (Hz)

IR = 200µA

TJ = 25°C

LM4041-1.2

= V

OUT

REF

RS 30k

V

1Hz rate

IN

LM4041-1.2

V

R

Test Circuit

LM4040/4041 10 January 2000

LM4040/4041 Micrel

T

LM4041 T ypical Characteristics

Reference Voltage vs. Output

Voltage and Temperature

1.244

25°C

1.240

1.236

85°C

-40°C

1.232

1.228

1.224

REFERENCE VOLTAGE (V)

1.220
0 2 4 6 8 10

OUTPUT VOLTAGE (V)

LM4041-ADJ

Output Saturation

1.7
LM4041-ADJ

= V

V

1.6

ADJ

1.5

1.4

1.3

1.2

1.1

OUTPUT SATURATION (V)

1.0

0 2 4 6 8 10 12

+ 5µV

REF

-40°C

25°C

OUTPUT CURRENT (mA)

85°C

85°C

-40°C

Reference Voltage vs.

Temperature and Output Voltage

1.244

LM4041-ADJ

IR = 1mA

1.240

1.236

1.232

V

= V

OUT

REF

V

= 5V

OUT

1.228
V

= 10V

1.224

OUT

REFERENCE VOLTAGE (V)

1.220

-40 -20 0 20 40 60 80 100
TEMPERATURE (°C)

Output Impedence

vs. Frequency *

1K

100

10

V

OUT

IMPEDANCE (Ω)

1

1.23V

0

100 1k 10k 100k 1M

LM4041-ADJ

= 25 °C

T

J

I

= 1mA

R

∆I

= 0.1I

R

= 10V

5V

2.5V

FREQUENCY (Hz)

R

CL = 0

=1µF

C

L

X

C

Feedback Current vs.

Output Voltage and Temperature

100

LM4041-ADJ

80

TJ = 85°C

60

40

FEEDBACK (nA)

20

TJ = 25°C, -40°C

0

0 2 4 6 8 10

OUTPUT VOLTAGE (V)

Output Impedence

vs. Frequency *

1K

100

10

IMPEDANCE (Ω)

1

0

100 1k 10k 100k 1M

LM4041-ADJ
T

V

= 10V

OUT

5V

2.5V

1.23V

FREQUENCY (Hz)

= 25 °C

J

I

= 1mA

R

∆I

= 0.1 I

R

CL = 0

R

=1µF

C

L

X

C

Reverse Characteristics

FB STEPS (V)

0 2 4 6 8

100

80

60

40

20

REVERSE CURRENT (µA)

0

0 2 4 6 8 10

TJ = 25°C
LM4041-ADJ

OUTPUT VOLTAGE (V)

Large Signal Response

-40°C

10

8
6
4

VOLTAGE (V)

2
0

0 10 20 30 40

RESPONSE TIME (µs)

LM4041-ADJ

OUTPUT

INPUT

T

= -40°C

J

-40°C

25°C
85°C

†

I

R

( + )

LM4041-ADJ

FB

( – )

2V / step

V

†

Reverse Characteristics

Test Circuit

V

OU

C

L

* Output Impedance vs. Freq.

Test Circuit

I

R

+

120k
FB

–

‡

+ 15V

5.1k

INPUT

100k

‡

Large Signal Response

FB

( + )

LM4041 - ADJ

( - )

V

OUT

Test Circuit

January 2000 11 LM4040/4041

LM4040/4041 Micrel

k

Applications Information

The LM4040 and LM4041 have been designed for stable
operation without the need of an external capacitor con­nected between the (+) and (–) pins. If a bypass capacitor is
used, the references remain stable.

Schottky Diode

LM4040-x.x and LM4041-1.2 in the SOT-23 package have a
parasitic Schottky diode between pin 2 (–) and pin 3 (die
attach interface connect). Pin 3 of the SOT-23 package must
float or be connected to pin 1. LM4041-ADJs use pin 3 as the
(–) output.

Conventional Shunt Regulator

In a conventional shunt regulator application (see Figure 1),
an external series resistor (RS) is connected between the
supply voltage and the LM4040-x.x or LM4041-1.2 reference.
RS determines the current that flows through the load (IL) and
the reference (IQ). Since load current and supply voltage may
vary, RS should be small enough to supply at least the
minimum acceptable IQ to the reference even when the
supply voltage is at its minimum and the load current is at its
maximum value. When the supply voltage is at its maximum
and IL is at its minimum, RS should be large enough so that
the current flowing through the LM4040-x.x is less than
15mA, and the current flowing through the LM4041-1.2 or
LM4041-ADJ is less than 12mA.

RS is determined by the supply voltage (VS), the load and
operating current, (IL and IQ), and the reference’s reverse
breakdown voltage (VR).

Rs = (Vs – VR) / (IL + IQ)

Adjustable Regulator

The LM4041-ADJ’s output voltage can be adjusted to any
value in the range of 1.24V through 10V. It is a function of the
internal reference voltage (V

) and the ratio of the external

REF

feedback resistors as shown in Figure 2. The output is found
using the equation

(1) VO = V

´ [ (R2/R1) + 1 ]

REF

where VO is the desired output voltage. The actual value of
the internal V

is a function of VO. The “corrected” V

REF

REF

is

determined by
(2) V
where VO is the desired output voltage. ∆V

´ = VO (∆V

REF

/ ∆VO) + V

REF

Y

/ ∆VO is found

REF

in the Electrical Characteristics and is typically –1.3mV/V and
VY is equal to 1.233V. Replace the value of V

´ in equation

REF

(1) with the value found using equation (2).
Note that actual output voltage can deviate from that pre-

dicted using the typical ∆V
grade parts, the worst-case ∆V

/ ∆VO in equation (2); for C-

REF

/ ∆VO is –2.5mV/V and

REF

VY = 1.248V.
The following example shows the difference in output voltage

resulting from the typical and worst case values of
∆V

/ ∆VO:

REF

Let VO = +9V. Using the typical values of ∆V

REF

/∆VO , V

REF

is 1.223V. Choosing a value of R1 = 10kΩ, R2 = 63.272kΩ.
Using the worst case ∆V

/ ∆VO for the C-grade and D-

REF

grade parts, the output voltage is actually 8.965V and 8.946V
respectively. This results in possible errors as large as 0.39%
for the C-grade parts and 0.59% for the D-grade parts. Once
again, resistor values found using the typical value of
∆V

/ ∆VO will work in most cases, requiring no further

REF

adjustment.

FB

λ

R1
120

R2
1M

< –12V
LED ON

LM4041-ADJ

D1

+

–

R3
200

–5V

Figure 3. Voltage Level Detector

ADJ

+

–

R3
330

–5V

λ

D1

LM4041-

Figure 4. Voltage Level Detector

FB

R1
120k

R2
1M

> –12V
LED ON

LM4040/4041 12 January 2000

LM4040/4041 Micrel

V

IN

R1I

LM4041-ADJ

D2
1N457

R3
1M

R2
330k

V

OUT

LM4041-ADJ

FB

+

–

FB

–

+

D1
1N457

R4
330k

V

IN

R1

I

V

R2

50µA

LM4041-ADJ

D1
1N914

+

FB

–

OUT

D2
1N914

R3
240k

R4
240k

LM4041-ADJ

+

FB

–

D1
1N457

V

IN

I

R1

V

R2
510k

R3

FB

–

+

OUT

D2
1N457

LM4041-ADJ

510k

Figure 5. Fast Positive Clamp

LM4041-ADJ

2.4V + ∆V

R3
500k

+

FB

–

D1
1N457

I

D1

V

IN

R1

R2
390k

R4
390k

FB

–

+

Figure 7. Bidirectional Adjustable Clamp

±18V to ±2.4V

0 to 20mA

R1

390Ω

1N4002

± 2%

D2

D1* 1

V

OUT

D2
1N457

LM4041-ADJ

FB

λ

+

LM4041-ADJ

–

Figure 6. Bidirectional Clamp

±2.4V

Figure 8. Bidirectional Adjustable Clamp

±2.4 to ±6V

+ 5V

R2

6

470k

N.C.

January 2000 13 LM4040/4041

I

THRESHOLD

2

3

N.C.

=

1.24V
R1

5µA

+

4N28 GAIN

4N28

= 3.2mA

5

CMOS

4

Figure 9. Floating Current Detector

LM4040/4041 Micrel

+15V

0 to 20 mA

D2

1N4002

+

LM4041-ADJ

–

R2

120k

1µA < I

OUT

I

Figure 10. Current Source

R1

332Ω

±1%

1N914

2N2222

R2

22k

FB

+

LM4041-ADJ

–

1

FB

2N
3964

= 100mA

1.24V

=

OUT

R1

2N2905

R1

+5V

R3
100k

6

D1*

N.C.

2

3

4N28

I

THRESHOLD

1.24V

=

R1

λ

= 3.7mA ± 2%

Figure 11. Precision Floating Current Detector

* D1 can be any LED, VF = 1.5V to 2.2V at 3mA. D1 may act as an indicator. D1 will

be on if I

THRESHOLD

falls below the threshold current, except with I = O.

5

CMOS

R4

4

10M

LM4040/4041 14 January 2000

LM4040/4041 Micrel

Package Information

C

L

2.36 (0.093)

2.28 (0.090)

3.05 (0.120)

2.67 (0.105)

0.445 (0.0175) TYP 3 PLACES

1.40 (0.055)

1.19 (0.047)

C

L

1.15 (0.045)

0.76 (0.030)

0.10 (0.004)

0.013 (0.0005)

2.50 (0.098)

2.10 (0.083)

8°
0°

DIMENSIONS:

MM (INCH)

0.15 (0.006)

0.076 (0.0030)

0.41 (0.016)

0.13 (0.005)

SOT-23 (M3)

January 2000 15 LM4040/4041

LM4040/4041 Micrel

MICREL INC. 1849 FORTUNE DRIVE SAN JOSE, CA 95131 USA

TEL + 1 [phone] FAX + 1 [phone] WEB http://www.micrel.com

This information is believed to be accurate and reliable, however no responsibility is assumed by Micrel for its use nor for any infringement of patents or

other rights of third parties resulting from its use. No license is granted by implication or otherwise under any patent or patent right of Micrel Inc.

© 2000 Micrel Incorporated

LM4040/4041 16 January 2000